<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <div id="app">
    <div>
      <p>请选择你要购买的书籍</p>
      <ul>
        <li v-for="v of arr" :key="v.name">
          <span>{{ v.name }}</span>
          <button @click="v.count++">买书</button>
        </li>
      </ul>
      <table border="1" width="500" cellspacing="0">
        <tr>
          <th>序号</th>
          <th>书名</th>
          <th>单价</th>
          <th>数量</th>
          <th>合计</th>
        </tr>
        
        <tr v-for="v, i of arr" :key="v.name">
          <th>{{ i + 1 }}</th>
          <th>{{ v.name }}</th>
          <th>{{ v.price }}</th>
          <th>{{ v.count }}</th>
          <th>{{ v.price * v.count }}</th>
        </tr>

      </table>
      <p>总价格为: {{ totalMoney }}</p>
    </div>
  </div>
  <script src="./vue.js"></script>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        arr: [
          {
            name: "水浒传",
            price: 107,
            count: 0,
          },
          {
            name: "西游记",
            price: 192,
            count: 0,
          },
          {
            name: "三国演义",
            price: 219,
            count: 0,
          },
          {
            name: "红楼梦",
            price: 178,
            count: 0,
          },
        ],
      },
      computed: {
        totalMoney() {
          return this.arr.reduce((sum, v) => {
            return sum + v.price * v.count
          }, 0)
        }
      },
    })
  </script>
</body>

</html>